The present invention relates to a thermally conductive interface material that is interposed between a source of heat, such as an electronic component and a heat sink. The most common example of this invention is the use of a thermal material between a semiconductor device and a heat sink so that heat generated by the semiconductor can be removed.
Typically, silicone or urethane binders filled with one or more thermally conductive materials are used as the thermal interface. One such product is commercially known as CHO-THERM.RTM. thermally conductive materials, available from Chomerics, Inc.
In placing the thermally conductive material between the heat source and the heatsink, care must be taken to ensure that no air becomes trapped between the thermally conductive material and the adjacent substrate. Air is a notoriously poor conductor of heat and its presence reduces the ability of the thermally conductive material to transport heat from its source to its sink. This can lead to an overheating of the heat source. Moreover, the overheating will be localized at the spot where the air is trapped, causing the overheating to be concentrated in a small area making it more intense and its effects more devastating, especially to electronic components.
Moreover to ensure that air is not trapped, such thermally conductive interface materials are applied individually by hand. This is a labor extensive, slow process. Additionally, the assembly can only be done with fairly large components which contain a means for attaching them to the heat source, such as screws, rivets, etc.
Therefore, there is a need for a thermally conductive material that will eliminate the problem of air becoming trapped between the thermal material and the adjacent substrate and a method for forming a heat transferring assembly.
Moreover, there is a need for a process that will speed up the assembly of thermally conductive electroinc packages and for products that will provide thermal conductivity to smaller electronic assemblies.